There can be no acquisition of an easement by prescription (or title to property by adverse possession) unless the person claiming same used the property openly, hostile, and in defiance of the landowner's rights.
>> There can be no secret easement by prescription.
>> If the access was used with the landowner's permission then there can be no easement by prescription (ditto adverse possession).
An easement (or title to land) must be for 20 years unbroken, uninterrupted and totally open and hostile and in defiance of the landowner's rights to exclusive possession of their property.
If the subject access road to the back 80 acres has been done in a friendly way with the landowner simply agreeing to it then there is no and can be no easement by prescription, adverse possession rights, etc.
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Philosophical commentary: If someone claims to be Christian, a conservative or a constitutionalist then they should by definition never make a claim for any kind of title by adverse possession/easement by prescription rights/title, etc.
Doing same would be a direct contradiction of the aforementioned beliefs and principles IMO.
You are pretty much spot on, however, the wild card is what one of these crazy Alabama Juries might do.